(1) Field of the Invention
This invention relates to a non-aqueous electrolyte battery including a spiral electrode body which is provided by winding both a band-shaped negative electrode, using a light metal such as lithium, sodium, etc as an active material, and a band-shaped positive electrode, using manganese dioxide, carbon fluoride, etc as an active material, through a separator.
(2) Description of the Prior Art
Batteries of this kinds provided with the spiral electrode body have an advantage of taking high current discharge therefrom as compared with button type or flat type batteries. However, since a separator interposed between positive and negative electrodes is generally composed of materials with comparatively low melting point such as non-woven fabrics or sheets of non-aqueous electrolyte resisting polypropylene (m.p: 165.degree. to 170.degree. C.) or polyethylene (m.p: 130.degree. to 140.degree. C.), it may be melted by generation of heat within the battery caused by high current discharge or external short-circuiting, so that internal short-circuiting may bring about.
In U.S. Pat. No. 3,298,871, there has been disclosed a battery structure with a spiral electrode body, taking a nickel-cadmium battery as an example, which is prevented from short-circuiting, caused by piercing of separators by rough edges or burrs in the spirally wound cell roll or cracking of electrodes at both end edges when manufactured, by covering the both end edges of band-shaped electrodes with a sheet of regenerated cellulose or the like. However, the sheet is not employed in order to prevent the short-circuiting which might be caused by melt or fusion of separators. Particularly, since the regenerated cellulose concretely disclosed is carbonized by heat and becomes conductive, the short-circuiting caused by melt of separators can not be prevented.